First of all, pressure isn't measured in newtons. Pressure is force PER UNIT AREA. Force is measured in newtons, therefore pressure is measured in newtons per square metre (also known as pascals).

As for your question...come on! Seriously?!? You don't know what the typical atmospheric pressure is? Don't you ever watch the weather channel? Heh...I'm kind of joking around with you a bit, but even if you DON'T know it off the top of your head, it's something easily looked up. Here are two examples of how you could have saved me some time:

Nope, not quite. The area of their foot is what you are trying to calculate (this is a hypothetical person whose foot exerts a pressure equal to atmospheric pressure). So, what information do you need to calculate that area? Well, you need P, and you need F. You know P (it has been given). You DON'T know F. So, what do you need to find out?

Right, so to calculate A, you need BOTH F and P. But right now, you have only P. When the question says, "What do you need to ask?", it is asking you what additional information you need to solve this problem. Since you need both F and P, but you have only P, the additional information that you need is F. You can't solve the problem until you have F.

Now, what is F? How could you find it out (again, hypothetically)?

Note: this is a simple problem. They just have deliberately NOT given you all of the information you need to solve it. By asking you what additional information is required, they are just checking to see if you understand what the problem is asking.